A debate over the role of race in the current criticism of President Obama is forcing the White House to confront a volatile issue it would rather avoid.

On Tuesday, former president Jimmy Carter declared racism to be the subtext of many of the attacks being lobbed at the president, and members of the Congressional Black Caucus are pointing to race as a driving force behind the current level of animosity.

But at the White House, the official line is: Race issue? What race issue?

"I'm not sure I see this large national conversation going on right now," White House press secretary Robert Gibbs said Wednesday. He said Obama "does not believe that that criticism comes based on the color of his skin," attributing it instead to honest policy disagreements.

The criticism at issue includes a movement questioning Obama's citizenship, the rancor at last month's town hall meetings on health care and protests in which Obama has been likened to Adolf Hitler. Suspicions were confirmed for many African Americans last week when Rep. Joe Wilson (R-S.C.) shouted "You lie!" at Obama as he addressed Congress.

On Wednesday, Gibbs told reporters that Carter's remarks did not merit a broader discussion about why protesters had grown so hostile toward the nation's first African American president. And in the Oval Office, Obama declined to respond to a reporter's question about Carter's comments.

The reasons for the White House silence are varied, stemming largely from Obama's own measured approach to race. As a candidate, Obama rarely spoke about race overtly, projecting an image that his advisers hoped would appeal to all Americans and avoiding actions that might highlight the divide that still exists between blacks and whites.

When he finally did deliver a landmark race speech, in March 2008, it was in response to an uproar caused by his association with the Rev. Jeremiah A. Wright Jr., his controversial African American former pastor.

As the campaign wore on, however, Obama's supporters occasionally entertained the topic of race, particularly in response to what they saw as insensitive remarks about him, and by the end of 2008 the campaign had asked some black supporters to stop protesting in forceful terms for fear of a backlash.

On Wednesday, Gibbs said the White House has not asked members of the black caucus to stop ascribing a racist motive to Obama critics. Those comments have fueled a debate this week that has distracted from the president's main priority, health-care legislation.

Gibbs rejected a comparison to another race-related incident earlier this year, when Obama's friend Henry Louis Gates Jr., a Harvard professor, was arrested by a white Cambridge, Mass., police officer. Obama's remark that the officer had "acted stupidly" touched off an uproar that similarly shifted public focus from his health-care effort. The president summoned the pair to the White House and described it as a moment the nation could learn from. This time, however, Obama sees no such moment, Gibbs said.

That is not stopping the rest of the political establishment. Carter, a civil rights champion raised in the South, said Tuesday that "an overwhelming portion of the intensely demonstrated animosity toward President Barack Obama is based on the fact that he is a black man."